Dahlia imperialis or Bell tree dahlia is a member of the Dahlia genus native to Mexico, Central America and Colombia. It is a magnificent plant, reaching around 15-20 Ft, with thick, bamboo-like stems and single, downward pointing, pinkish-purple, orange-centered flowers in November/December. An attraction-seeking and rewarding plant.
It is a tuberous, herbaceous perennial, rapidly growing from the base after a dormant winter period, developing brittle, cane-like, 4-angled stems with swollen nodes and large tripinnate leaves, those near the ground soon being shed. The pendant or nodding flowerheads are 3-5" across with ray florets pink or mauvish-pink in color.
This species is fast-growing, the growth spurt being linked to shorter daylight hours, and usually comes into flower in autumn before the first frost. Propagation is by seed or by stem cuttings. Coming from warmer climes, it can be grown outside to zone 8+.